1. Field of the Invention
The invention relates to shielded power cable fitting in general and more particularly to a push-on end termination for cable conductors of sector-shaped cross section.
2. State of the Art
In order to be able to quickly assemble end terminations to plastic insulated, shielded power cables, in particular cables used in the voltage range from 10 to 30 kV, there have recently been developed prefabricated parts which merely need be pushed onto the appropriately prepared cable end. These include insulating parts made of a silicone rubber or of a synthetic rubber of the ethylene or propylene type in which a field controlling element (deflector) is embedded. The insulating parts, first developed for cable conductors of round cross section, are provided with a bore, the inside diameter of which is smaller than the outside diameter of the cable conductor stripped of the outer conducting layer. When pushing the insulating part on the cable conductor, the former is stretched elastically, thus assuring a firm, electrically safe seat of the push-on termination on the cable conductor.
Such push-on terminations have also been used on conductors of sector-shaped wire and conductor section of the type commonly used in 10 kV cables (Technische Mitteilungen AEG-Telefunken, 68 (1978) No. 3/4, page 170). Considering the sector shape of the cable conductors, however, difficulties are encountered in assuring an all around firm seat of the push-on termination on the cable conductor. To overcome this difficulty, it has been proposed to first apply a shrinkable adapter to the cable end which itself completely adapts inside to the sector-shaped section of the wire or conductor, has a cylindrical outside surface, and onto which a rotationally symmetrical push-on end termination can be pushed. The adapter may consist of a shrinkable part having a cylindrical outside and inside surface, and of nonshrinkable extrusions which adapt themselves to the sector wire or sector conductor and are rounded towards the outside (DE-GM 74 26 756).